Exhibit
      10.1 

    


     FIRST
      AMENDMENT TO COMMON STOCK PURCHASE AGREEMENT

    


    THIS
      FIRST AMENDMENT TO COMMON STOCK PURCHASE AGREEMENT
      (the
“Amendment”), dated as of July 23, 2008, by and between HEMISPHERX
      BIOPHARMA, INC.,
      a
      Delaware corporation (the “Company”), and FUSION
      CAPITAL FUND II, LLC,
      an
      Illinois limited liability company (the “Buyer”). Capitalized terms used herein
      and not otherwise defined herein shall have the meanings given to them in the
      Common Stock Purchase Agreement.

    


    WHEREAS,
      the
      parties hereto are parties to a Common Stock Purchase Agreement dated as of
      July
      2, 2008 (the “Common Stock Purchase Agreement”) pursuant to which the Buyer has
      agreed to purchase, and the Company has agreed to sell up to $30,000,000 of
      the
      Common Stock;

    


    WHEREAS,
      the
      parties desire to amend the Common Stock Purchase Agreement; 

    


    NOW,
      THEREFORE,
      in consideration of the agreements, covenants and considerations contained
      herein, the parties hereto agree as follows:


    


    
      	 	
              1.

            	
              Amendments.
                

            


    

    


    Section
      1(g) is hereby amended and restated in its entirety as follows:

    


    (g) Compliance
      with Principal Market Rules.
      Notwithstanding any other provision of this Agreement, the Company shall not
      effect any sale under this Agreement or be obligated to register under the
      1933
      Act Purchase Shares under this Agreement and the Buyer shall not have the right
      or the obligation to purchase shares of Common Stock under this Agreement to
      the
      extent that after giving effect to such purchase the "Exchange Cap" shall be
      deemed to be reached. The "Exchange Cap" shall be deemed to have been reached
      if, at any time prior to the shareholders of the Company approving the
      transaction contemplated by this Agreement, upon a purchase under this
      Agreement, the Purchase Shares and Commitment Shares issuable pursuant to such
      purchase would, together with all Purchase Shares and Commitment Shares
      previously issued under this Agreement, and any Common Stock previously issued
      to Fusion that would be aggregated by the American Stock Exchange exceed
      14,823,651 shares of Common Stock (19.99% of the 74,155,334 outstanding shares
      of Common Stock as of the date of this Agreement). The Company may, but shall
      be
      under no obligation to, request its shareholders to approve the transaction
      contemplated by this Agreement. The Company shall not be required to issue
      any
      shares of Common Stock or register any shares of Common Stock under this
      Agreement if such issuance or registration would breach the Company's
      obligations under the rules or regulations of the Principal Market.

     

    
      
        
        

      

      
        
        

        
          

        

      

      
        
        

      

    

     

    Section
      3(c) is hereby amended and restated in its
      entirety as follows:

     

    (c) Capitalization.
      As of
      the date hereof, the authorized capital stock of the Company consists of (i)
      200,000,000 shares of Common Stock, of which as of the date hereof, 74,155,334
      shares are issued and outstanding, none are held as treasury shares, 16,446,992
      shares are reserved for issuance pursuant to the Company's stock option plans
      of
      which only approximately 8,883,524 shares remain available for future grants
      and
      9,731,275 shares are issuable and reserved for issuance pursuant to securities
      (other than stock options issued pursuant to the Company's stock option plans)
      exercisable or exchangeable for, or convertible into, shares of Common Stock
      and
      (ii) 5,000,000 shares of blank check Preferred Stock, $0.01 par value, of which
      as of the date hereof no shares are issued and outstanding . All of such
      outstanding shares have been, or upon issuance will be, validly issued and
      are
      fully paid and nonassessable. Except as disclosed in Schedule 3(c), (i) no
      shares of the Company's capital stock are subject to preemptive rights or any
      other similar rights or any liens or encumbrances suffered or permitted by
      the
      Company, (ii) there are no outstanding debt securities, (iii) there are no
      outstanding options, warrants, scrip, rights to subscribe to, calls or
      commitments of any character whatsoever relating to, or securities or rights
      convertible into, any shares of capital stock of the Company or any of its
      Subsidiaries, or contracts, commitments, understandings or arrangements by
      which
      the Company or any of its Subsidiaries is or may become bound to issue
      additional shares of capital stock of the Company or any of its Subsidiaries
      or
      options, warrants, scrip, rights to subscribe to, calls or commitments of any
      character whatsoever relating to, or securities or rights convertible into,
      any
      shares of capital stock of the Company or any of its Subsidiaries, (iv) there
      are no agreements or arrangements under which the Company or any of its
      Subsidiaries is obligated to register the sale of any of their securities under
      the 1933 Act (except the Registration Rights Agreement), (v) there are no
      outstanding securities or instruments of the Company or any of its Subsidiaries
      which contain any redemption or similar provisions, and there are no contracts,
      commitments, understandings or arrangements by which the Company or any of
      its
      Subsidiaries is or may become bound to redeem a security of the Company or
      any
      of its Subsidiaries, (vi) there are no securities or instruments containing
      anti-dilution or similar provisions that will be triggered by the issuance
      of
      the Securities as described in this Agreement and (vii) the Company does not
      have any stock appreciation rights or "phantom stock" plans or agreements or
      any
      similar plan or agreement. The Company has furnished to the Buyer true and
      correct copies of the Company's Certificate of Incorporation, as amended and
      as
      in effect on the date hereof (the "Certificate of Incorporation"), and the
      Company's By-laws, as amended and as in effect on the date hereof (the
      "By-laws"), and summaries of the terms of all securities convertible into or
      exercisable for Common Stock, if any, and copies of any documents containing
      the
      material rights of the holders thereof in respect thereto.


    


    
      	 	
              2.

            	
              Effect
                of Amendment/Incorporation of Certain Provisions.
                Except as amended as set forth above, the Common Stock Purchase Agreement
                shall continue in full force and effect. The provisions set forth
                in
                Section 11 of the Common Stock Purchase Agreement are hereby expressly
                incorporated by reference into this
                Amendment.

            


    

     

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    IN
      WITNESS WHEREOF,
      the
      Buyer and the Company have caused this First Amendment to Common Stock Purchase
      Agreement to be duly executed as of the date first written
      above.


    


    
      	 	
              THE
                COMPANY:

            
	 	 
	 	
              HEMISPHERX
                BIOPHARMA, INC.

            
	 	 
	 	
              By: 
                /s/ William
                A.
                Carter                                    

            
	 	
              Name:
                William A. Carter

            
	 	
              Title:
                Chief Executive Officer

            
	 	 
	 	
              BUYER:

            
	 	 
	 	
              FUSION
                CAPITAL FUND II, LLC

            
	 	
              BY:
                FUSION CAPITAL PARTNERS, LLC

            
	 	
              BY:
                ROCKLEDGE CAPITAL CORPORATION

            
	 	 
	 	
              By:
                /s/
                Josh
                Scheinfeld                                       

            
	 	
              Name:
                Josh Scheinfeld

            
	 	
              Title:
                  President

            


    

     

    
      
        
        

      

      
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